Exemplary embodiments of the present invention relate to a method and device for protecting a vehicle occupant in a vehicle seat of a vehicle.
PCT publication WO 03/033 294 A1 describes a vehicle seat that effects a lateral displacement of the occupant sitting on the vehicle seat in the event of a lateral impact or immediately before a lateral impact. The sideways displacement is in a direction away from the vehicle side facing the impact and towards the center of the vehicle. In order to achieve the sideways displacement at least one seat cushion can be moved transversely in relation to the seat attachment and independently of other seat components.
PCT publication WO 2008/110610 A1 describes a vehicle seat assembly for a vehicle comprising a vehicle seat, at least one inflatable element arranged on the vehicle seat, means for inflating the inflatable element that, in response to a control signal signaling an impending collision of the vehicle with an object, inflate the inflatable element. The inflatable element is configured and arranged in such a way that, as it is being inflated in response to the control signal, it exerts an impulse on a vehicle occupant sitting on the vehicle seat, which impulse moves the vehicle occupant away from a collision section of the vehicle about to collide with the object. In addition PCT publication WO 2008/110610 A1 describes a method for protecting a vehicle occupant.
EPO publication EP 1 698 521 A1 describes a device and a method for protecting occupants in a vehicle.
Published German patent application DE 10 2005 032 033 A1 describes a vehicle occupant restraint system comprising a vehicle seat of which the backrest is laterally delimited by at least one side wall, wherein the transition region from a front side of the backrest to the side wall forms a support surface for a vehicle occupant, and further comprising an airbag module, the air bag of which is accommodated in a folded state in the backrest of the vehicle seat and the unfolding direction of which is oriented towards the support surface.
Exemplary embodiments of the present invention are directed to an improved, in particular more effective method and an improved device for protecting a vehicle occupant in a vehicle seat of a vehicle compared to those of the prior art.
In the method for protecting a vehicle occupant in a vehicle seat of a vehicle, in particular a passenger car, at least one protection element arranged on the vehicle seat and capable of being triggered in order to protect the vehicle occupant located on the vehicle seat is triggered in the event of an impending collision or in the event of a collision, wherein upon the triggering of the protection element, a motion impulse is exerted on the vehicle occupant or at least on a body section of the vehicle occupant, by which motion impulse the vehicle occupant or at least a body section of the vehicle occupant is moved away from a collision section of the vehicle that is colliding or about to collide with the object. According to the invention, the intensity of the motion impulse is varied in relation to a determined accident severity and/or an identified accident type.
The intensity of the motion impulse and the resulting force acting on the vehicle occupant can thus be adapted to the anticipated accident severity and/or to the anticipated accident type and consequently to a specific load level so that the vehicle occupant is not subjected to unduly strong impulses.
The protection element is preferably triggered and/or activated in response to a control signal that signals a collision or an impending collision of the vehicle with an object, or a predetermined braking of the vehicle.
In an embodiment of the invention, in the event of an identified increasing accident severity a stronger motion impulse and consequently a correspondingly longer displacement distance is set for the vehicle occupant. By evaluating sensors that detect at least one vehicle environment, the accident severity (i.e., degree of severity of the accident, i.e., slight or severe impact), and/or the accident type (i.e., 90° side collision in the case of a swerving vehicle or acute angle side collision in the case of drifting wheels of the vehicle), is/are determined. Preference is given to determination of the severity degree and/or of the accident type in stages. This enables a discriminating and variable triggering and control of the protection element, thus achieving a comfort function along with the protective function (displacement of the occupant).
In an exemplary improvement of the invention, the intensity of the motion impulse and the resulting displacement distance of the vehicle occupant is also set in relation to a determined vehicle state, in particular in relation to the speed of the vehicle itself.
An exemplary embodiment provides that in the event of an identified high accident severity and intense lateral dynamics of the vehicle, in particular a skidding of the vehicle, the protection element is triggered in a controlled manner in such a way that a stronger motion impulse is exerted, and consequently a longer displacement distance is achieved, than in the event of an identified low accident severity.
If the speed of the vehicle itself exceeds a presettable threshold, i.e., the vehicle is traveling at high speed, the triggering of the protection element is preferably deactivated, as lateral dynamics become irrelevant in driving situations in the high speed range.
In the event of an identified impending collision or a foresightedly identified collision, the protection element is preferably triggered in such a way that the displacement of the vehicle occupant is initiated before the collision occurs. An acceleration thus acts upon the vehicle occupant prior to the occurrence of the collision, thus reducing the accident energy exerted as a consequence of a collision; in other words, the absolute value of the accident energy and thus a stress and/or acceleration maximum of the vehicle occupant, and thus passenger stress resulting therefrom, are reduced.
With the device for protecting a vehicle occupant in a vehicle seat of a vehicle, in particular a passenger car, at least one protection element arranged on the vehicle seat and capable of being triggered for protecting the vehicle occupant sitting on the vehicle seat can be triggered in the event of an identified impending collision or in the event of an identified collision. According to the invention, a means for setting the intensity of the motion impulse that can be exerted by the protection element on the vehicle occupant or at least on a body section of the vehicle occupant can be set in relation to a determined accident severity and/or a determined accident type and consequently to a specific load level.
As a result of the motion impulse, the distance is increased between the vehicle occupant and a collision section of the vehicle that is colliding or about to collide with the object. By varying the intensity of the motion impulse, a value for increasing the distance between the vehicle occupant and a collision section of the vehicle that is colliding or about to collide with the object can advantageously be adapted to the accident severity and/or to the accident type.
The intensity of the motion impulse preferably corresponds to the accident severity and/or accident type determined by means of the at least one control unit and/or sensors for detecting a vehicle environment and/or a vehicle state. In order to set the intensity of the motion impulse relative to the determined accident severity and/or accident type, the setting mechanism is coupled to the control unit and/or to the sensors.
As protection elements, preference is given to the vehicle seat having two opposite inflatable elements in the side walls, wherein only the inflatable element facing the anticipated collision site is triggered and inflated towards the vehicle occupant in response to the control signal. This ensures that the motion impulse is expressed in the predetermined intensity. The vehicle occupant is displaced by the inflated element towards the interior of the vehicle and thus away from the deforming side region of the vehicle, e.g., the door lining or B-post.
As protection elements, preference is given to the vehicle seat having two opposite, movable armrests arranged on the vehicle seat, wherein only the armrest facing the anticipated collision site is triggered and moved towards the vehicle occupant in response to the control signal. With the movable armrest, the motion impulse can be applied to the whole surface of the vehicle occupant.
A restraining of the vehicle occupant is thus initiated much sooner than with a standard restraint system. Additionally, the vehicle occupant participates as soon as possible in the acceleration effected by the triggering of the protection element and acceleration peaks are thus reduced.
Essentially no relative speed is built up between the inflatable element and the vehicle occupant. Hence the relative speed between the vehicle occupant and the side zone of the vehicle is also always less than in a standard protection device with a vehicle occupant restraint system.
In a particularly advantageous embodiment, the invention allows an inflation of the inflatable element or a movement of the displaceable element and thus a displacement of the vehicle occupant away from the collision point in particular in response to a so-called pre-crash signal, before the vehicle actually collides with the object. By the inflating or moving element, the vehicle occupant is moved out of his/her seated position away from the collision section of the vehicle, i.e., the collision point, generating an additional distance between the vehicle occupant and the collision point. This additional distance represents an additional absorption distance, whereby the effects of the collision on the vehicle occupant are reduced. Additionally, the relative speed between the vehicle occupant and the vehicle structure intruding into the interior of the vehicle due to the collision can be reduced by the displacement of the vehicle occupant. In this process, the distance traveled by the vehicle occupant away from the collision point towards the vehicle interior can be used as an additional deformation distance in the event of a collision.